Emails aren’t private, so much should be known by now. When you communicate via email, the contents are not only visible to yours and the other side’s email providers, but potentially also to numerous others like the NSA who intercepted your email on the network. Encrypting emails is possible via PGP or S/MIME, but neither is particularly easy to deploy and use. Worse yet, both standard were found to have security deficits recently. So it is not surprising that people and especially companies look for better alternatives.
It appears that the German company FTAPI gained a good standing in this market, at least in Germany, Austria and Switzerland. Their website continues to stress how simple and secure their solution is. And the list of references is impressive, featuring a number of known names that should have a very high standard when it comes to data security: Bavarian tax authorities, a bank, lawyers etc. A few years ago they even developed a “Secure E-Mail” service for Vodafone customers.
I now had a glimpse at their product. My conclusion: while it definitely offers advantages in some scenarios, it also fails to deliver the promised security.